When stenosis or occlusion occurs in vascular channels such as the blood vessel, or when the blood vessel is blocked by thrombus, angioplasty (PTA: Percutaneous Transluminal Angioplasty and PTCA: Percutaneous Transluminal Coronary Angioplasty) by which stenosis site or occlusion site is expanded with a balloon catheter and improves blood flow at angioperiphery side has been conventionally found in many operative examples in medical organizations and is general as the remedy for such diseases.
Atherectomy remedy in which atheroma is cut by transcatheter has been carried out in accordance with the progress of devices such as DCA (Directional Coronary Atherectomy) and a rotor brator. Further, there have been many stents and the like that are placed for keeping the patency state of the expanded stenosis site and occlusion site. These PTCA, Atherectomy remedy, stenting and the like are named generically as percutaneous coronary intervention (PCI). Cases with high difficulty such as the legion of left coronary main trunk (LMT) and the legion of chronic total occlusion (CTO) have been the adaptation of PCI.
The contrast medium is an indispensable drug at coronary angiography (CAG) and PCI and used widely. On the other hand, it has been known that the contrast medium has side reactions such as renal function disorder, cutaneous disorder, cardiovascular disorder, respiratory apparatus disorder and urinary organs disorder. Consequently, there has been carried out tries for suppressing the use amount of the contrast medium as little as possible by using an injector and the like.
However, angiography cycles are increased in cases with high difficulty such as the LMT legion and CTO legion and the use amount of the contrast medium is increased inevitably. Further, drug eluting stent (DES) dramatically reducing the occurrence of restenosis after the stenting has been recently developed and is resulting in high remedy effect, but it is status quo that much more contrast medium is used for the accurate grasping of legion properties such as blood vessel diameter and length and the positioning of DES for the legion at the deployment of DES.
It has been recently reported that the complication of diabetics is found in many patients carrying out PCI and the renal function disorder is a problem among the side reactions by the contrast medium. Hydration before and after PCI, the administration of N-acetylcysteine and the like and the removal of the contrast medium by dialysis after PCI have been tried for kidney failure patients in particular, in order to suppress the renal function disorder called as the contrast induced nephropathy.
Among these, it is considered that dialysis is an effective means for removing the contrast medium in the blood but there has been reported that its effect is questionable. As presented in Coronary Intervention, Vol. 2, No.4, (2003) pp78 to 83, difference in the frequency of occurrence of the contrast induced nephropathy is not confirmed between a group (dialysis group) in which dialysis was carried out for chronic kidney failure patients after use of the contrast medium and a group (non dialysis group) in which no dialysis was carried out. Since time from the administration of the contrast medium to dialysis is long, it is suggested that the blood containing the contrast medium continues to circulate in the body and it is cause for provoking the renal function disorder. From these backgrounds, a remedy system that reduces load to the kidney by the contrast medium during PCI is required and related technology is developed.
Japanese Unexamined Patent Publication No. 7-303701 discloses a balloon catheter equipped with an expandable balloon, catheter lumen extended from a proximal portion to a distal portion and a catheter main body having the catheter lumen extending from the proximal portion to the balloon, wherein a plurality of opening hole portions penetrated in the fore-mentioned catheter lumen at the edge side from the balloon of the catheter main body are provided.
FIG. 13 shows the sectional schematic diagram of the heart. The purpose of a conventional catheter 17 for extraction is that it is arranged at the coronary sinus opening 16 through the right atrium 15 from inferior vena cava 14, blood flow from the coronary sinus opening 16 to the right atrium 15 is blocked by expanding the balloon nearly at the same time with the administration of the contrast medium to the coronary artery and the blood containing the contrast medium administrated in the coronary artery is collected from the catheter lumen. The contrast medium in the blood collected is removed by adsorption and filtration, and the load to kidney by the contrast medium can be reduced by hydrating the blood after removal in the body. However, the conventional catheter 17 for extraction had a problem below.
Firstly, it is difficult to expand the balloon at the coronary sinus opening 16 and block the blood flow to the right atrium 15. The coronary artery is connected to the arteriolae and circulated to the venulae through capillary blood vessel. The several arteriolae converge to form the great cardic vein, middle cardic vein, minor cardic vein and the like and converge to the coronary sinus together with residual venulae to be flown in the right atrium 15. Extremely many veins flow in the coronary sinus and flow-in site is extended over a wide range until nearby the coronary sinus opening 16. Namely, when the balloon is expanded in the inside of the coronary sinus, the blood from venulae converging nearby the coronary sinus opening 16 is not blocked, flows into the right atrium 15 and it is difficult to introduce the blood in the catheter lumen.
Further, since the wall of the coronary sinus is very thin, there is possibility of provoking the damage of wall and perforation by expansion of the balloon. When the damage and perforation are generated, the blood flow out between the heart and pericardial membrane and dangerousness of provoking severe disease such as cardiac tamponade is heightened.
On the other hand, it is very difficult to accurately arrange the balloon at a position surely covering the coronary sinus opening 16 and to arrange the balloon by fixation, because of the influence of cardiac beat. Accordingly, in case of a balloon catheter related to prior art, it is difficult to block the blood flow from the coronary sinus to the right atrium 15 and introduce it to the catheter lumen, and as a result, the capture rate of the contrast medium administrated in the coronary artery is lowered.
Further, when the blood containing the contrast medium administrated in the coronary artery is extracted by the catheter 17 during PCI, it is necessary to introduce devices for blood access such as a sheath introducer and a deployment needle at least at 3 positions, summing a site at which the catheter is inserted, a site where the extracted blood is returned and further, a site to which a guiding catheter used for PCI. Thus, since the number of introducing the devices for blood access is much more than usual PCI, it has been also a problem that the degree of invasion to a patient is high.